These changes are the raw update to linux-4.4.6-rt14. Kernel sources
[kvmfornfv.git] / kernel / fs / nilfs2 / alloc.c
index 8df0f3b..2ccbf55 100644 (file)
@@ -133,38 +133,38 @@ nilfs_palloc_bitmap_blkoff(const struct inode *inode, unsigned long group)
 
 /**
  * nilfs_palloc_group_desc_nfrees - get the number of free entries in a group
- * @inode: inode of metadata file using this allocator
- * @group: group number
  * @desc: pointer to descriptor structure for the group
+ * @lock: spin lock protecting @desc
  */
 static unsigned long
-nilfs_palloc_group_desc_nfrees(struct inode *inode, unsigned long group,
-                              const struct nilfs_palloc_group_desc *desc)
+nilfs_palloc_group_desc_nfrees(const struct nilfs_palloc_group_desc *desc,
+                              spinlock_t *lock)
 {
        unsigned long nfree;
 
-       spin_lock(nilfs_mdt_bgl_lock(inode, group));
+       spin_lock(lock);
        nfree = le32_to_cpu(desc->pg_nfrees);
-       spin_unlock(nilfs_mdt_bgl_lock(inode, group));
+       spin_unlock(lock);
        return nfree;
 }
 
 /**
  * nilfs_palloc_group_desc_add_entries - adjust count of free entries
- * @inode: inode of metadata file using this allocator
- * @group: group number
  * @desc: pointer to descriptor structure for the group
+ * @lock: spin lock protecting @desc
  * @n: delta to be added
  */
-static void
-nilfs_palloc_group_desc_add_entries(struct inode *inode,
-                                   unsigned long group,
-                                   struct nilfs_palloc_group_desc *desc,
-                                   u32 n)
+static u32
+nilfs_palloc_group_desc_add_entries(struct nilfs_palloc_group_desc *desc,
+                                   spinlock_t *lock, u32 n)
 {
-       spin_lock(nilfs_mdt_bgl_lock(inode, group));
+       u32 nfree;
+
+       spin_lock(lock);
        le32_add_cpu(&desc->pg_nfrees, n);
-       spin_unlock(nilfs_mdt_bgl_lock(inode, group));
+       nfree = le32_to_cpu(desc->pg_nfrees);
+       spin_unlock(lock);
+       return nfree;
 }
 
 /**
@@ -239,6 +239,26 @@ static int nilfs_palloc_get_block(struct inode *inode, unsigned long blkoff,
        return ret;
 }
 
+/**
+ * nilfs_palloc_delete_block - delete a block on the persistent allocator file
+ * @inode: inode of metadata file using this allocator
+ * @blkoff: block offset
+ * @prev: nilfs_bh_assoc struct of the last used buffer
+ * @lock: spin lock protecting @prev
+ */
+static int nilfs_palloc_delete_block(struct inode *inode, unsigned long blkoff,
+                                    struct nilfs_bh_assoc *prev,
+                                    spinlock_t *lock)
+{
+       spin_lock(lock);
+       if (prev->bh && blkoff == prev->blkoff) {
+               brelse(prev->bh);
+               prev->bh = NULL;
+       }
+       spin_unlock(lock);
+       return nilfs_mdt_delete_block(inode, blkoff);
+}
+
 /**
  * nilfs_palloc_get_desc_block - get buffer head of a group descriptor block
  * @inode: inode of metadata file using this allocator
@@ -277,6 +297,22 @@ static int nilfs_palloc_get_bitmap_block(struct inode *inode,
                                      &cache->prev_bitmap, &cache->lock);
 }
 
+/**
+ * nilfs_palloc_delete_bitmap_block - delete a bitmap block
+ * @inode: inode of metadata file using this allocator
+ * @group: group number
+ */
+static int nilfs_palloc_delete_bitmap_block(struct inode *inode,
+                                           unsigned long group)
+{
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       return nilfs_palloc_delete_block(inode,
+                                        nilfs_palloc_bitmap_blkoff(inode,
+                                                                   group),
+                                        &cache->prev_bitmap, &cache->lock);
+}
+
 /**
  * nilfs_palloc_get_entry_block - get buffer head of an entry block
  * @inode: inode of metadata file using this allocator
@@ -295,6 +331,20 @@ int nilfs_palloc_get_entry_block(struct inode *inode, __u64 nr,
                                      &cache->prev_entry, &cache->lock);
 }
 
+/**
+ * nilfs_palloc_delete_entry_block - delete an entry block
+ * @inode: inode of metadata file using this allocator
+ * @nr: serial number of the entry
+ */
+static int nilfs_palloc_delete_entry_block(struct inode *inode, __u64 nr)
+{
+       struct nilfs_palloc_cache *cache = NILFS_MDT(inode)->mi_palloc_cache;
+
+       return nilfs_palloc_delete_block(inode,
+                                        nilfs_palloc_entry_blkoff(inode, nr),
+                                        &cache->prev_entry, &cache->lock);
+}
+
 /**
  * nilfs_palloc_block_get_group_desc - get kernel address of a group descriptor
  * @inode: inode of metadata file using this allocator
@@ -332,51 +382,40 @@ void *nilfs_palloc_block_get_entry(const struct inode *inode, __u64 nr,
 
 /**
  * nilfs_palloc_find_available_slot - find available slot in a group
- * @inode: inode of metadata file using this allocator
- * @group: group number
- * @target: offset number of an entry in the group (start point)
  * @bitmap: bitmap of the group
+ * @target: offset number of an entry in the group (start point)
  * @bsize: size in bits
+ * @lock: spin lock protecting @bitmap
  */
-static int nilfs_palloc_find_available_slot(struct inode *inode,
-                                           unsigned long group,
+static int nilfs_palloc_find_available_slot(unsigned char *bitmap,
                                            unsigned long target,
-                                           unsigned char *bitmap,
-                                           int bsize)
-{
-       int curr, pos, end, i;
-
-       if (target > 0) {
-               end = (target + BITS_PER_LONG - 1) & ~(BITS_PER_LONG - 1);
-               if (end > bsize)
-                       end = bsize;
-               pos = nilfs_find_next_zero_bit(bitmap, end, target);
-               if (pos < end &&
-                   !nilfs_set_bit_atomic(
-                           nilfs_mdt_bgl_lock(inode, group), pos, bitmap))
-                       return pos;
-       } else
-               end = 0;
-
-       for (i = 0, curr = end;
-            i < bsize;
-            i += BITS_PER_LONG, curr += BITS_PER_LONG) {
-               /* wrap around */
-               if (curr >= bsize)
-                       curr = 0;
-               while (*((unsigned long *)bitmap + curr / BITS_PER_LONG)
-                      != ~0UL) {
-                       end = curr + BITS_PER_LONG;
-                       if (end > bsize)
-                               end = bsize;
-                       pos = nilfs_find_next_zero_bit(bitmap, end, curr);
-                       if ((pos < end) &&
-                           !nilfs_set_bit_atomic(
-                                   nilfs_mdt_bgl_lock(inode, group), pos,
-                                   bitmap))
+                                           unsigned bsize,
+                                           spinlock_t *lock)
+{
+       int pos, end = bsize;
+
+       if (likely(target < bsize)) {
+               pos = target;
+               do {
+                       pos = nilfs_find_next_zero_bit(bitmap, end, pos);
+                       if (pos >= end)
+                               break;
+                       if (!nilfs_set_bit_atomic(lock, pos, bitmap))
                                return pos;
-               }
+               } while (++pos < end);
+
+               end = target;
+       }
+
+       /* wrap around */
+       for (pos = 0; pos < end; pos++) {
+               pos = nilfs_find_next_zero_bit(bitmap, end, pos);
+               if (pos >= end)
+                       break;
+               if (!nilfs_set_bit_atomic(lock, pos, bitmap))
+                       return pos;
        }
+
        return -ENOSPC;
 }
 
@@ -475,15 +514,15 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode,
        void *desc_kaddr, *bitmap_kaddr;
        unsigned long group, maxgroup, ngroups;
        unsigned long group_offset, maxgroup_offset;
-       unsigned long n, entries_per_group, groups_per_desc_block;
+       unsigned long n, entries_per_group;
        unsigned long i, j;
+       spinlock_t *lock;
        int pos, ret;
 
        ngroups = nilfs_palloc_groups_count(inode);
        maxgroup = ngroups - 1;
        group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
        entries_per_group = nilfs_palloc_entries_per_group(inode);
-       groups_per_desc_block = nilfs_palloc_groups_per_desc_block(inode);
 
        for (i = 0; i < ngroups; i += n) {
                if (group >= ngroups) {
@@ -501,8 +540,8 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode,
                n = nilfs_palloc_rest_groups_in_desc_block(inode, group,
                                                           maxgroup);
                for (j = 0; j < n; j++, desc++, group++) {
-                       if (nilfs_palloc_group_desc_nfrees(inode, group, desc)
-                           > 0) {
+                       lock = nilfs_mdt_bgl_lock(inode, group);
+                       if (nilfs_palloc_group_desc_nfrees(desc, lock) > 0) {
                                ret = nilfs_palloc_get_bitmap_block(
                                        inode, group, 1, &bitmap_bh);
                                if (ret < 0)
@@ -510,12 +549,12 @@ int nilfs_palloc_prepare_alloc_entry(struct inode *inode,
                                bitmap_kaddr = kmap(bitmap_bh->b_page);
                                bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
                                pos = nilfs_palloc_find_available_slot(
-                                       inode, group, group_offset, bitmap,
-                                       entries_per_group);
+                                       bitmap, group_offset,
+                                       entries_per_group, lock);
                                if (pos >= 0) {
                                        /* found a free entry */
                                        nilfs_palloc_group_desc_add_entries(
-                                               inode, group, desc, -1);
+                                               desc, lock, -1);
                                        req->pr_entry_nr =
                                                entries_per_group * group + pos;
                                        kunmap(desc_bh->b_page);
@@ -573,6 +612,7 @@ void nilfs_palloc_commit_free_entry(struct inode *inode,
        unsigned long group, group_offset;
        unsigned char *bitmap;
        void *desc_kaddr, *bitmap_kaddr;
+       spinlock_t *lock;
 
        group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
        desc_kaddr = kmap(req->pr_desc_bh->b_page);
@@ -580,13 +620,15 @@ void nilfs_palloc_commit_free_entry(struct inode *inode,
                                                 req->pr_desc_bh, desc_kaddr);
        bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page);
        bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
+       lock = nilfs_mdt_bgl_lock(inode, group);
 
-       if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group),
-                                   group_offset, bitmap))
-               printk(KERN_WARNING "%s: entry number %llu already freed\n",
-                      __func__, (unsigned long long)req->pr_entry_nr);
+       if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap))
+               nilfs_warning(inode->i_sb, __func__,
+                             "entry number %llu already freed: ino=%lu\n",
+                             (unsigned long long)req->pr_entry_nr,
+                             (unsigned long)inode->i_ino);
        else
-               nilfs_palloc_group_desc_add_entries(inode, group, desc, 1);
+               nilfs_palloc_group_desc_add_entries(desc, lock, 1);
 
        kunmap(req->pr_bitmap_bh->b_page);
        kunmap(req->pr_desc_bh->b_page);
@@ -611,6 +653,7 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode,
        void *desc_kaddr, *bitmap_kaddr;
        unsigned char *bitmap;
        unsigned long group, group_offset;
+       spinlock_t *lock;
 
        group = nilfs_palloc_group(inode, req->pr_entry_nr, &group_offset);
        desc_kaddr = kmap(req->pr_desc_bh->b_page);
@@ -618,12 +661,15 @@ void nilfs_palloc_abort_alloc_entry(struct inode *inode,
                                                 req->pr_desc_bh, desc_kaddr);
        bitmap_kaddr = kmap(req->pr_bitmap_bh->b_page);
        bitmap = bitmap_kaddr + bh_offset(req->pr_bitmap_bh);
-       if (!nilfs_clear_bit_atomic(nilfs_mdt_bgl_lock(inode, group),
-                                   group_offset, bitmap))
-               printk(KERN_WARNING "%s: entry number %llu already freed\n",
-                      __func__, (unsigned long long)req->pr_entry_nr);
+       lock = nilfs_mdt_bgl_lock(inode, group);
+
+       if (!nilfs_clear_bit_atomic(lock, group_offset, bitmap))
+               nilfs_warning(inode->i_sb, __func__,
+                             "entry number %llu already freed: ino=%lu\n",
+                             (unsigned long long)req->pr_entry_nr,
+                             (unsigned long)inode->i_ino);
        else
-               nilfs_palloc_group_desc_add_entries(inode, group, desc, 1);
+               nilfs_palloc_group_desc_add_entries(desc, lock, 1);
 
        kunmap(req->pr_bitmap_bh->b_page);
        kunmap(req->pr_desc_bh->b_page);
@@ -679,22 +725,6 @@ void nilfs_palloc_abort_free_entry(struct inode *inode,
        req->pr_desc_bh = NULL;
 }
 
-/**
- * nilfs_palloc_group_is_in - judge if an entry is in a group
- * @inode: inode of metadata file using this allocator
- * @group: group number
- * @nr: serial number of the entry (e.g. inode number)
- */
-static int
-nilfs_palloc_group_is_in(struct inode *inode, unsigned long group, __u64 nr)
-{
-       __u64 first, last;
-
-       first = group * nilfs_palloc_entries_per_group(inode);
-       last = first + nilfs_palloc_entries_per_group(inode) - 1;
-       return (nr >= first) && (nr <= last);
-}
-
 /**
  * nilfs_palloc_freev - deallocate a set of persistent objects
  * @inode: inode of metadata file using this allocator
@@ -708,9 +738,18 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
        unsigned char *bitmap;
        void *desc_kaddr, *bitmap_kaddr;
        unsigned long group, group_offset;
-       int i, j, n, ret;
+       __u64 group_min_nr, last_nrs[8];
+       const unsigned long epg = nilfs_palloc_entries_per_group(inode);
+       const unsigned epb = NILFS_MDT(inode)->mi_entries_per_block;
+       unsigned entry_start, end, pos;
+       spinlock_t *lock;
+       int i, j, k, ret;
+       u32 nfree;
 
        for (i = 0; i < nitems; i = j) {
+               int change_group = false;
+               int nempties = 0, n = 0;
+
                group = nilfs_palloc_group(inode, entry_nrs[i], &group_offset);
                ret = nilfs_palloc_get_desc_block(inode, group, 0, &desc_bh);
                if (ret < 0)
@@ -721,38 +760,89 @@ int nilfs_palloc_freev(struct inode *inode, __u64 *entry_nrs, size_t nitems)
                        brelse(desc_bh);
                        return ret;
                }
-               desc_kaddr = kmap(desc_bh->b_page);
-               desc = nilfs_palloc_block_get_group_desc(
-                       inode, group, desc_bh, desc_kaddr);
+
+               /* Get the first entry number of the group */
+               group_min_nr = (__u64)group * epg;
+
                bitmap_kaddr = kmap(bitmap_bh->b_page);
                bitmap = bitmap_kaddr + bh_offset(bitmap_bh);
-               for (j = i, n = 0;
-                    (j < nitems) && nilfs_palloc_group_is_in(inode, group,
-                                                             entry_nrs[j]);
-                    j++) {
-                       nilfs_palloc_group(inode, entry_nrs[j], &group_offset);
-                       if (!nilfs_clear_bit_atomic(
-                                   nilfs_mdt_bgl_lock(inode, group),
-                                   group_offset, bitmap)) {
-                               printk(KERN_WARNING
-                                      "%s: entry number %llu already freed\n",
-                                      __func__,
-                                      (unsigned long long)entry_nrs[j]);
+               lock = nilfs_mdt_bgl_lock(inode, group);
+
+               j = i;
+               entry_start = rounddown(group_offset, epb);
+               do {
+                       if (!nilfs_clear_bit_atomic(lock, group_offset,
+                                                   bitmap)) {
+                               nilfs_warning(inode->i_sb, __func__,
+                                             "entry number %llu already freed: ino=%lu\n",
+                                             (unsigned long long)entry_nrs[j],
+                                             (unsigned long)inode->i_ino);
                        } else {
                                n++;
                        }
-               }
-               nilfs_palloc_group_desc_add_entries(inode, group, desc, n);
+
+                       j++;
+                       if (j >= nitems || entry_nrs[j] < group_min_nr ||
+                           entry_nrs[j] >= group_min_nr + epg) {
+                               change_group = true;
+                       } else {
+                               group_offset = entry_nrs[j] - group_min_nr;
+                               if (group_offset >= entry_start &&
+                                   group_offset < entry_start + epb) {
+                                       /* This entry is in the same block */
+                                       continue;
+                               }
+                       }
+
+                       /* Test if the entry block is empty or not */
+                       end = entry_start + epb;
+                       pos = nilfs_find_next_bit(bitmap, end, entry_start);
+                       if (pos >= end) {
+                               last_nrs[nempties++] = entry_nrs[j - 1];
+                               if (nempties >= ARRAY_SIZE(last_nrs))
+                                       break;
+                       }
+
+                       if (change_group)
+                               break;
+
+                       /* Go on to the next entry block */
+                       entry_start = rounddown(group_offset, epb);
+               } while (true);
 
                kunmap(bitmap_bh->b_page);
-               kunmap(desc_bh->b_page);
+               mark_buffer_dirty(bitmap_bh);
+               brelse(bitmap_bh);
 
+               for (k = 0; k < nempties; k++) {
+                       ret = nilfs_palloc_delete_entry_block(inode,
+                                                             last_nrs[k]);
+                       if (ret && ret != -ENOENT) {
+                               nilfs_warning(inode->i_sb, __func__,
+                                             "failed to delete block of entry %llu: ino=%lu, err=%d\n",
+                                             (unsigned long long)last_nrs[k],
+                                             (unsigned long)inode->i_ino, ret);
+                       }
+               }
+
+               desc_kaddr = kmap_atomic(desc_bh->b_page);
+               desc = nilfs_palloc_block_get_group_desc(
+                       inode, group, desc_bh, desc_kaddr);
+               nfree = nilfs_palloc_group_desc_add_entries(desc, lock, n);
+               kunmap_atomic(desc_kaddr);
                mark_buffer_dirty(desc_bh);
-               mark_buffer_dirty(bitmap_bh);
                nilfs_mdt_mark_dirty(inode);
-
-               brelse(bitmap_bh);
                brelse(desc_bh);
+
+               if (nfree == nilfs_palloc_entries_per_group(inode)) {
+                       ret = nilfs_palloc_delete_bitmap_block(inode, group);
+                       if (ret && ret != -ENOENT) {
+                               nilfs_warning(inode->i_sb, __func__,
+                                             "failed to delete bitmap block of group %lu: ino=%lu, err=%d\n",
+                                             group,
+                                             (unsigned long)inode->i_ino, ret);
+                       }
+               }
        }
        return 0;
 }